gps error in mexico


#1

i notice that, when using my garmin to track our progress (in a bus) in Yucatan that my GPS showed us off the highway a few miles when in fact we were on it…maybe they dont have good sat reception there? Otherwise the unit worked pretty well, though I also noticed that I couldnt get the city detail like I can here in the conus. My model is the Garmin 250w and it (supposedly) comes with US, Canada, and Mexico.


#2

alternatively the map may have had the highway in the wrong location (perhaps it was repaved on an alternate alignment and the map company never figured it out).


#3

Skelly76, sometimes due to bad satellite geometry in the sky if your GPS is not WAAS enabled, you might be off as far as 20~30 meters, but to be off by a few miles, I would suspect that it might be map problem.


#4

I lost gps signal today going into Puebla. Both FMS’s went into dead reckoning mode. First time this has happened to me and I have spent a lot of time in places more remote than Mexico. They worked fine going out.


#5

I don’t think it has to do with the remoteness of a place. I’ve been in many remote places where I got great GPS signals. It all has to do with the satellites.

Garmin has an article at www8.garmin.com/aboutGPS/ about why you received a degraded signal.


#6

Shame on you for not checking RAIM


#7

GPS, RAIM.
Man am I glad we don’t have any of that high tech stuff. :cry:


#8

+1

Maps for Mexico are nothing more than basemap detail and are not very accurate. According to some of my GPS tracks in South and Central America, I have walked on water many times! :smiley:


#9

I was standing on Lincoln St in South Beach. Not on a boat, which would’ve been much better…


#10

If you had a marine map it would have figured it out!


#11

On the other hand my maxipad had us right on the taxiway the other night. Kind of cheating since it was using assisted GPS by then.


#12

You use maxi pads??? T.M.I. :open_mouth:


#13

It was beautiful VFR, I was enjoying the view of the Volcanoes, and had it backed up with VHF raw data on the RMI’s. Had there been any weather I would have used the ILS anyways & you’ve shown off your handheld to us before I know you don’t have RAIM monitoring or approach capabilities with that.


#14

HAHA- we only use that for the XM weather, we have approach capable GPS’s on the pedestal.

The Problem with the Trimble isn’t RAIM it’s a matter of RAM…